Polymeric polycarboxylic acids



Patented Jan. 24, 1967 United States Patent ice 33044444,4'bis(4-hydroxyphenyl)-pentanoic acid epiclilorohydrin 3,300,444 l"POLYMERIC POLYCARBOXYLIC ACIDS 0 oomonor-rorn- Sylvan O. Greenlee,Racine, Wis., assignor to Aqueous S. C. Johnson & Son, Inc., Racine,Wis. 5 N0 Drawing. Filed Oct. 3, 1955, Ser. No. 538,245 N aOH 14 Claims.(Cl. 260-47) This invention relates to a new class of polycarboxylicacids. More particularly this invention relates to the poly- C mericcondensation products of diaryloxy-substituted acids v g, \cmcHzc 02H nm Aqueous 4,4-bis(4-hydroxyphenyl)-pentanoic acidbis(4-hydroxyphenyl)-is0propylidene 1,4-dichlorobutane W F o 0 CHgOHzCHzCHgO o CHzCHzCHzCHz n lo; CH3 CHQCHQC 02H Ca \CH3 I1 IV andcoupling agents which are bifunctional with respect wherein the value of11, indicating the degree of polyrnto aromatic hydroxyl groups.erization, depends on the quantities of reactants em- An object of thisinvention is to provide a novel class of ployed but has been found torepresent a value of less than resinous acids having high meltingpoints. about 15. The compound shown at IV illustrates one Anotherobject of this invention is to provide a novel method of obtaining alower acid number should it be class of resinous compositions, havinghigh acid values, necessary for a particular use. which are capable offurther modifiication to suit a partic- The end groups in all of theabove polycarboxylic acids ular need. will vary depending on the ratioof hydroxyaryl-substi- A specific object of this invention is to providea new tuted acid to aliphatic coupling agent. If excess of the polymericpolycarboxylic acid by condensing an hyformer is used, for example, inreaction with dichlorodroxyarlyl-substituted acid with a coupling agentwhich butene, the end groups will be phenolic hydroxyl groups. containsat least two reactive groups capable of forming If, on the other hand,dichlorobutene is used in excess, the an ether linkage with an aromatichydroxyl group. end groups will be chlorobutene groups.

The Preferred Products of the invention are Polymeric Thearyloxy-substituted acid contemplated for use herepolycarboxyl organicacids which contain a number of .in should ha e two hydroxyaryl groupsatta h d t a molecules of bis(arylene)-substituted aliphatic acidcousingle carbon atom. The preparation of such an aryloxy pled to oneanother through ether oxygen by alkylene or acid is most convenientlycarried out by condensing a substituted alkylene radicals. .Suchcompositions may be keto-acid with the desired phenol. Experience in theprepared, for example, by heating a bis( hydroxyaryl)- preparation ofbisphenol and related compounds indicates substituted aliphatic acidsuch as 4,4-bis(4-hydroxyphenthat the carbonyl group of the keto-acidshould be posiyl)-pentanoic acid, in the presence of alkali, with aditioned next to a terminal carbon atom in order to obtain functionalcoupling agent such as a di-halohydrin, di-halide, satisfactory yields.It is to be understood that the termior an epihialohydrin. Illustrativepossible polycarboxylic nal carbon atom referred to is a primary carbonatom, acids are the following: i.e., one having three hydrogen atomsattached thereto. i 1 mbutene Prior application, Serial Nos. 464,607 and489,300, filed 4'4bls(hydr;xyphenynmam m dcho October 25, 1954, andFebruary 18, 1955, both now -o OCH2OH=CHCH2 abandoned, respectively,disclose a number of illustrative Aqueous compounds suitable for use asthe aryloxy-substituted acid and methods of preparing the same. Thesema- NaOH terials, which are referred to for convenience as diphenolicacids or DPA, consist of the condensation products of levulinic acid andphenol, substituted phenols, or mixtures thereof. It is to be understoodthat the phenolic nuclei of the diphenolic acids may be substituted withany CH3 0112011200211 I groups which will not interfere with thereactions con- V templated. For example, the nuclei may be alkylated44'bs(flydroxiphenyl)'pemanolc amd dlchlomdletllyl ether with alkylgroups of from 1-5 carbon atoms as disclosed OCHgCHzOCHzCHgin mycopending application Serial No. 489,300 or they may be halogenated. Thediphenolic acids derived from Aqueous NaOH substituted phenols, such asthe alkylated phenols, are sometimes more desirable than the productsobtained from unsubstituted phenols since the alkyl groups providebetter organic solvent solubility, flexibility, and water-resistance.However, the unsubstituted product is usually 7 C more readily purified.Q, \cHzoHzcmH i H The coupling agents advantageously used in building upthe desired molecular structure of the subject resinous polycarboxylicacids must be bifunctional in their reactions with phenolic hydroxylgroups in the presence of alkali. Exemplary coupling agents having thischaracteristic are the aliphatic dihalides. The reaction of a phenolichydroxyl group with an alkyl halide forms an ether linkage by the wellknown Williamson synthesis, employing an alkali metal phenoxide:

@om CzHsCl oo2r-r5 NaCl Similarly, the use of a dihalide and a dihydricphenol results in a polymeric structure having alternating aryl andalkyl nuclei joined to one another by ether oxygen linkages.

It should thus be apparent that virtually any dihalide constitutes asuitable coupling agent for present purposes, provided that it containno substituents which will interfere with the etherification reaction.Illustrative dihalides are 1,2-dichloroethane, 1,3-dichloropropane,1,4-dichlorbutane, 1,4-dichlorobutene, glycerol dichlorohydrin, theoxy-dihalides wherein one of the carbon atoms is replaced by oxygen oris hydroxylated, such as the alkylene halohydrins or ethers, such asbis(2-chloroethyl)ether, and the corresponding dihalides of otherhalogens, including saturated and unsaturated compounds containing up toabout carbon atoms.

An additional class of coupling agents operable herein includes thesimple difunctional epoxy compounds since the epoxide group is known tobe converted by a phenolic hydroxyl group, forming an ether linkage.Preferred epoxy compounds are the epihalohydrins such as epichlorohydrinor epibromohydrin. Also suitable are the oxy-epihalohydrins wherein oneof the carbon atoms is replaced by ether oxygen, as illustrated by2,3-epoxypropyl-2-hydroxy-3-chloropropyl ether.

Reaction of the diphenolic acids with dihalides or epihalohydrins iscarried out in the presence of suflicient alkali, such as sodiumhydroxide, to neutralize the carboxyl group of the diphenolic acid andto react with the halogen group of the halide or halohydrin. Toillustrate, the reaction of one mol of a diphenolic acid with one mol ofepichlorohydrin would require 2 mols of sodium hydroxide, one toneutralize the carboxyl group, and one to take up the chlorine ionsliberated by epichlorohydrin in the reaction. Similarly, the reaction oftwo mols of a diphenolic acid with 1 mol of a dichloride would requirefour mols of sodium hydroxide. Usually, in practice alkali is usedsomewhat in excess of the theoretical amounts. Such alkaline reactionsare conveniently carried out in aqueous solution; however, highly polarorganic solvents may be used. These reactions, involving the interactionof halides with sodium phenoxide to form ether linkages, are preferablycarried out at temperatures ranging from 7515 0C. Reaction of an activehalogen group, such as that in epichlorohydrin, and the simultaneousreaction of its epoxide group with a diphenolic acid to give thepolybasic acids might, for example, be carried out at temperatures offrom 75-100 C. for periods of 30 minutes to an hour. The reaction ofactive chlorides, such as 1,4- dichlorobutene, with the sodium phenoxiedgroups may also be carried out at relatively low temperatures of around100 C. for short periods of time, of about 1 hour. The use of lessreactive halides, such as 1,4-dichlorobutane, on the other hand,requires more vigorous reaction conditions of several hours heating atabout 100 C., or of higher temperatures for shorter periods of time.

A class of coupling agents not mentioned above is that of the simplealiphatic polyepoxides. Their use, however, requires much more care toneutralize the carboxyl group of the diphenolic acid, either byesterification or salt formation, to prevent it from taking part in thereaction. The reaction is conveniently carried out by heating theneutralized diphenolic acid with the polyepoxide at temperatures of from-200 C., usually in the ab- 75 sence of any solvent. However, ifdesired, organic solvents may be used provided they do not containfunctional groups which would interfere with the reaction of the epoxidegroup with the phenolic hydroxyl group. Where simple polyepoxides arereacted with, for example, methyl or ethyl ester of diphenolic acid, itmay be desirable to use traces of catalyst, such as boron trifluorideadducts, to speed up reaction of the epoxide group with the phenolichydroxyl groups.

Examples I to X inclusive illustrate the preparation of thepolycarboxylic acids of this invention. It will be noted that the firstsix examples represent polycarboxylic acids which are free of alcoholichydroxyl groups, while Examples VII to X inclusive describe thepreparation of polycarboxylic acids containing alcoholic hydroxyl groupswithin the same molecule. Examples V, VI, and X describe the preparationof polycarboxylic acids by the reaction with aliphatic coupling agentsof mixtures of a diphenolic acid and a dihydric phenol containing nocarboxyl group. These dihydric phenols can be defined asbis(hydroxyaryl) gem alkanes. Proportions expressed expressed refer toparts by weight unless otherwise indicated.

Example I In a reaction vessel provided with a thermometer, a mechanicalagitator, and a reflux condenser was added 500 parts of water and 124parts of sodium hydroxide. With continuous agitation 286 parts of4,4-bis(4-hydroxyphenyl)-pentanoic acid was added, and after completelydissolved, 63 parts of 1,4-dichlorobutene-2 was added. The continuouslyagitated mixture was refluxed for 4 hours, after which the excesscaustic was neutralized with HCl. The aqueous layer was removed bydecantation and the organic acid layer freed from salt by washing fourtimes with hot water. The resinous product was finally freed from thelast traces of water by drying in an oven. The resulting product had asoftening point of C. (Durrans Mercury Method, Journal of Oil & ColourChemists Association, 12, 173175 [1929]), and an acid value of 165. Acidvalue as used herein is defined as the number of milligrams of KOHrequired to neutralize the acidity of one gram of the sample.

Example 11 In a similar manner a solution of 286 parts of 4,4-bis(4-hydroxyphenyl)-pentanoic acid dissolved in an aqueous alkali solutionprepared from 124 parts of sodium hydroxide and 400 parts of water wasrefluxed for 6 hours with 64 parts of 1,4-dichlorobutane. A-fterneutralization with HCl and washing free of salt, the product was freedfrom the last traces of Water by heating with continuous agitation untilthe temperature had risen to C. The resulting product had an acid valueof 163 and a softening point of 117 C.

Example III In an autoclave provided with a mechanical agitator wasplaced 1500 parts of water, 300 parts of sodium hydroxide, 858 parts of4,4-bis(4-hydroxyphenyl)-pentanoic acid, and 286 parts ofbis(2-chloroethyl) ether. The autoclave was closed and the reactionmixture heated with agitation at C. for a period of 5 hours. Thereaction mixture was cooled to below 100 C. so as to release pressureand the product was neutralized with HCl. The aqueous layer was removedby decantation and the resinous product washed four times with hot waterto remove sodium chloride. The product was finally freed from the lasttraces of water by heating with continuous agitation to a temperature of130 C. The product had a softening point of 72 C. and an acid value of147.

Example IV A mixture of 1144 parts of 4,4-bis(4-hydroxyphenyl)-pentanoic acid, 320 parts of sodium hydroxide, 1500 parts of water, and286 parts of bis(2-chloroethyl)ether was treated in the manner describedin Example III and gave a product having a softening point of 69 C. andan acid value of 164.

Example V Following the procedure of Example III, a mixture of 342 partsof bis(4-hydroxyphenyl)-isopropylidine, 572 parts of4,4-bis(4-hydroxyphenyl)-pentanoic acid, 358 parts ofbis(2-chloroethyl)ether, 1500 parts of water, and 300 parts of sodiumhydroxidewas heated for 7 hours at 150 'C., neutralized, washed, anddried to give a product having a softening point of 59 C. and an acidvalue of 89.

- Example VI A mixture of 228 parts ofbis(4-hydroxyphenyl)-isopnopyli-dene, 572 parts of4,4-bis(4-hydroxyphenyl)-pentanoic acid, 286 parts ofbis(2-chloroethyl)ether, 1000 parts water, and 280 parts of sodiumhydroxide was treated as in Example III, except that it was heated for 6hours at 150 C. The product, after neutralization, washing, and drying,had an acid value of 118 and a softening point of 73 C.

Example VII In a flask provided with a thermometer, a mechanicalagitator, and a reflux condenser was added 800 parts of water, 80 partsof sodium hydroxide, and 286 parts of 4,4-bis(4-hydroxyphenyl)-pentanoic acid. After the diphenolic acid had alldissolved and at a temperature of 65 C., 75 parts of epichlorohydrin wasadded. With continuous agitation the temperature was gradually raised to90 C. and held at 90-95" C. for a period of 1 hour. The product wasneutralized with HCl and the aqueous layer removed by decantation. Afterwashing the product four times with hot water to remove the sodiumchloride, the product was freed from the last traces of water by heatingto a temperature of 110 C. This product had an acid value of 133.Although this product was a hard, brittle solid, softening points asdetermined on the products of Example I to V1 inclusive giveinconsistent results due to the fact that some interesterification ofthe alcoholic hyd-roxyl groups with the carboxylic acid groups takesplace when the product is heated to temperatures of 100 C. or higher.

. Example VIII A mixture of 286 parts of 4,4-bis(4-hydroxyphenyl)-pentanoic acid,'800 parts of water, 80 parts of sodium hydroxide and 69parts of epichlorohydrin, treated as in Example VII, gave a hard,brittle, resinous product having an acid value of 136.

Example IX Following the procedure set forth in Example VII, 3. mixtureof 286 parts of 4,4-bis(4-hydroxyphenyl)-pentanoic acid, 600 parts ofwater, 60* parts of sodium hydroxide, and 47 parts of epichlorohydringave a final product having an acid value of 162 and an initialsoftening point of 80 C.

3 Example X A mixture of 191. parts of 4,4-bis(4-hydroxyphenyl)-pentanoic acid, 76 parts of bis(4-hydroxyphenyl)isoprop-ropylidene, 62parts of epichlorohydrin, 600 parts of water, and 68 parts of sodiumhydroxide was treated in the manner set forth in Example VII and gave aproduct having an acid value of 108 and an initial softening point of105 C.

The polybasic acids of this invention are resinous in character,possessing relatively high melting points. The carboxyl groups of thesubject polycarboxylic acids are esterifiable with either alcoholichydroxyl groups or epoxide groups. The products thus may find utility inthe formulation of alkali-soluble resins for use in combination withother ingredients in making of removable coatings. It has been foundthat the polycarboxylic acids herein described are soluble in aqueousalkaline solutions usually employed in formulating such products, namelysodium hydroxide, ammonium hydroxide, and borax. A particularly valuableapplication of the subject polybasic acids has been found to be in theco-conversion products formed by the application of heat to combinationsof. these acids with various polyepoxides of the resinous or nonresinoustypes. Condensation products of the polycarboxylic acids, for example,with complex resinous epoxides prepared by the condensation ofepichlorohydrin with polyhydric phenols, produce infusible, insoluble.products of great commercial value as adhesives, protective coatings,and molded objects. A co-conversion product derived from the subjectpolycarboxylic acid and an epoxidized vegetable oil exhibits outstandingproperties, being hard, flexible and highly resistant to water, alkali,and hydrocarbon solvents. These products have the added advantage ofbeing capable of conversion during the film baking process, both throughthe olefin linkages and by esterification of the epoxide group.

The following example illustrates a method of preparing a typicalco-conversion product, and its utility and properties as a film.

Example XI Admex 710 (Archer-Daniels-Midland Company), an epoxidizedsoya bean oil, having an epoxide equivalent weight of 263, was dissolvedin methyl ethyl ketone to a nonvolatile content of 50%. A mixture of 3.7parts of this composition and 5 parts of the polycarboxylic acid ofExample I, spread in thin films and heat treated for a period of 1 hourat C., were tack-free and flexible. The film showed no deterioration onexposure to 5% aqueous sodium hydroxide for a period of 35 minutes or onexposure to boiling water for a period of 6. hours.

While there are above disclosed but a limited number of embodiments ofthe product of the invention herein presented, it is possible to producestill other embodiments without departing from the inventive conceptherein disclosed.

What is claimed is:

1. A resinous polycarboxylic acid ether having aliphatic chainsalternating with and connected by ether oxygen to residues of apentanoic acid obtained by the removal of the phenolic hydnoxyl, saidpentanoic acid consisting essentially of 4,4-bis(4-hydroxyaryl)pentanoic acid wherein the hydroxyaryl radical ishydroxyphenyl and is free from substituents other than alkyl groups offrom 15 carbon atoms, said aliphatic chains, being selected from thegroup consisting of hydrocarbon, oxyhydrocarbon, 3-hydroxyl substitutedhydrocarbon, and fl-hydroxyl substituted oxahydrocarbon radicals of 2-10carbon atoms, said fl-position being relative to said ether oxygen.

2. The composition of claim 1 wherein the pentanoic acid consistsessentially of 4,4-bis(4-hydroxyaryl)pentanoic acid wherein thehydroxyaryl radical is hydroxyphenyl and is free from substituents otherthan alkyl groups of one carbon atom.

3. The composition of claim 1 wherein the pentanoic acid is4,4-bis(4-hydroxyphenyl)pentanoic acid.

4. A resinous polycarboxylic acid ether prepared by reacting (l)epichlorohydrin and (2) 4,4-bis(4-hydroxyphenyl)pentanoic acid in analkaline medium, said ether containing only functional groups selectedfrom the group consisting of carboxyl and hydroxyl.

5. A resinous polycarboxylic acid ether prepared by reacting (1)dichloroethyl ether and (2) 4,4-bis(4-hydroxyphenyl)pentanoic acid in analkaline medium, said ether containing only functional groups selectedfrom the group consisting of carboxyl and hydroxyl.

6. A resinous polycarboxylic acid ether prepared by reacting (1)1,4-dichlorobutane and (2) 4,4-bis(4-hydroxyphenyl)pentanoic acid in analkaline medium, said ether containing only functional groups selectedfrom the group consisting of carboxyl and hydroxyl.

7. A resinous polycarboxylic acid ether prepared by reacting (1)1,4-dichlorobutene and (2) 4,4-bis(4-hy- 7 8 droxyphenyl)pentanoic acidin an alkaline medium, said hydroxyphenyl and is free from substituentsother than ether containing only functional groups selected from alkylgroups of from 1-5 carbon atoms in an alkaline the group consisting ofcarboxyl and hydroxyl. medium of sufficient strength to form a salt of aphenolic 8. A resinous composition of matter having the general hydroxylgroup. formula 5 12. A method of preparing a resinous polycarboxylic H Fo OR on X I Y XQY X Y X Y 063 oH2oI-ho00H n Cfia CHzOI-IzGOOH wherein Xand Y are members selected from the group acid ether comprising heatinga bis(haloalkyDether of consisting of hydrogen and alkyl groups of from1 to from 2-10 carbon atoms with a pentanoic acid consisting carbonatoms; R is an aliphatic divalent radical selected essentially of 4,4bis(4 hydroxyaryl)pentanoic acid from the group consisting ofhydrocarbon, oxahydrocarwherein the hydroxyaryl radical is hydroxyphenyland is bon, [3 hydroxyl substituted hydrocarbon, and ti hydr-oxyl freefrom substituents other than alkyl groups of from substitutedoxahydrocarbon radicals of 2-l0 carbon 15 carbon atoms in an alkalinemedium of suflicient atoms, said [3 position being relative to saidether oxygen, strength to form a salt of a phenolic hydroxyl group. andn has a value of less than about 15. 13. A resinous compositon of matterhaving the gen- 9. A resinous polycarboxylic acid ether having aliphaticeral formula z I- o |)-R- 0 oz X Y X Y X Y X Y 0E3 CH2CH2COOHv 11 Ol a\OH2CH2COOH chains alternating with and connected by ether oxygenwherein X and Y are members selected from the group to residues obtainedby the removal of phenolic hydroxyls consisting of hydrogen and alkylgroups of from 1-5 from a pentanoic acid and also from abis(hydroxycarbon atoms; R is an aliphatic divalent radical selectedphenyl) gem alkane, said pentanoic acid consisting esfrom the groupconsisting of hydrocarbon, oxahydrosentially of4,4-bis(4-hydroxyaryl)pentanoic acid wherein carbon, fi-hydroxylsubstituted hydrocarbon, and 5-hythe hydroxyaryl radical ishydroxyphenyl and is free from droxyl substituted oxahydrocarbonradicals of 210 carsubstituents other than alkyl groups of from l-5carbon bon atoms, said ,8 position being relative to said ether atoms,the residues of said bis(hydroxyphenyl) gem aloxygen; Z is a member ofthe group consisting of hydrokane containing only the elements carbonand hydrogen; gen and Wherein R is s a v defined and 11 said aliphaticchains being selected from the groups conhas a Value of less than aboutsisting of hydrocarbon, oxahydrocarbon, 5 hydroxyl sub- A Polymericcondensation Product P FP by stituted hydrocarbon, and /3 hydroxylsubstituted oxahyacting dlchloroflhyl ether a d (2)4,4-b1s(4-hydroxydrocarbon radicals of 2-10 carbon atoms, said 18position phenynpqnianoic acid in i alkaline medium Said Prodbeinqrelative to Said ether oxygen uct containing only funct1onal groupsselected from the 10. A method of preparing a resinous polycarboxylic 0group conslstmg of carboxyl and hydroxyl' azcildoethelg comtprisingligating at dichlorollkane from 5 References Cited by the Examiner caron a oms W1 a pen anoic act COIlSlS ing essentially of4,4-bis(4-hydroxyaryl)pentanoic acid wherein UNITED STATES PATENTS thehydroxyaryl radical is hydroxyphenyl and is free from 2,331,265 10/ 1943Coleman 611 250-47 substituents other than alkyl groups of from l-Scarbon 2,694,694 11/1954 Greenlee 260-17 atoms in an alkaline medium ofsufficient strength to WILLIAM H. SHORT, Primary Examinerform a salt ofa phenolic hydroxyl group. 1

11. A method of preparing a resinous polycarboxylic MiLTON STERMAN,PHILIP MANGAN, acid ether comprising heating an epihalohydrin with aExammempentanoic acid consisting essentially of 4,4-bis(4-hydroxy- G,KANTOROW, R J, BUTTERMARK J C aryl)pentanoic acid wherein t ehydroxyaryl rad cal is MARTlN, J, T, BROWN, Assistant Examiners.

1. A RESINOUS POLYCARBOXYLIC ACID ETHER HAVING ALIPHATIC CHAINSALTERNATING WITH AND CONNECTED BY ETHER OXYGEN TO RESIDUES OF APENTANOIC ACID OBTAINED BY THE REMOVAL OF THE PHENOLIC HYDROXYL, SAIDPENTANOIC ACID CONSISTING ESSENTIALLY OF 4,4-BIS(4-HYDROXYARYL)PENTANOICACID WHEREIN THE HYDROXYARYL RADICAL IS HYDROXYPHENYL AND IS FREE FROMSUBSTITUENTS OTHER THAN ALKYL GROUPS OF FROM 1-5 CARBON ATOMS, SAIDALIPHATIC CHAINS BEING SELECTED FROM THE GROUP CONSISTING OFHYDROCARBON, OXYHYDROCARBON, B-HYDROXYL SUBSTITUTED HYDROCARBON, ANDB-HYDROXYL SUBSTITUTED OXAHYDROCARBON RADICALS OF 2-10 CARBON ATOMS,SAID B-POSITION BEING RELATIVE TO SAID ETHER OXYGEN.